Machine for inserting plugs



M. W. HOWARD.

MACHINE FOR INSERTING PLUGS. APPLICATION FILED OCT. 1, 1918.

1,329,710, Patented Feb. 3,1920.

2 SHEETSSHEET I. 48

Fig. 2.

\nventor. Merton W. Howard WM snazm fmx Attys,

M. W. HOWARD.

MACHINE FOR INSERTING PLUGS.

APPLICATION FILED OCT. I, 1918.

1,329,? 10. Patented Feb. 3,1920.

i I 61 \nventor.

MevtonW. Howard by A'tLys.

UNITED PATENT OFFICE;

MERTON w. HOWARD, or LYNN, MAssAoHUsETTs, assrenon To A. E. LITTLE COMPANY, OF LYNN, MASSACHUSETTS,

A CORPORATION or MASSACHUSETTS.

MACHINE FOR INSER'IING PLUGS;

Specification of Letters Patent.

Patented Feb. 3, 1920.

Application filed October 1, 1918. Serial No. 256,482.

To all whom it may concern:

Be it known that l, lVlnn'roN N. HOWARD. a citizen of the United States, residing at Lynn county of Essex, State of ll lassachusetts, have invented an Improvement in Machines for Inserting Plugs, of which the :liollowing description, in connection with the accompanying drawing, is a specification, like characters on the drawing representing like parts.

T his invention relates to a machine for inserting plugs into articles. The plugs may be of dillerent shape and character and the articles into which these plugs are insorted may he of various kinds but the invention is more particularly designed for the inserting of hollow cylindrical rubber plugs into pockets in the sweat-band structure of helmets.

In the steel helmets in use by the Army it is desirable to provide a cushioning medium between the metal of the helmet and the head of the wearer. For this purpose it common to provide a sweat-band structure for the helmet made up of a strip oi leather or similar material juxtaposed upon a. base strip of material. with the hollow cylindrical plugs of rubber or similar material interposed at intervals between the strips. This leather strip is slitted transversely at regular intervals forming sections of about the length of a plug. Then the plugs are inserted through the slits in alternate sections. The process of inserting the plugs through the slits into place between the strips of the sweat-band is a tedious and difficult one especially as it is necessary that the plugs fit snugly when in place. The operation of inserting these plugs has heretofore been performed by hand and has required a large amount of labor and consequently adds materially to the cost of the article.

This invention provides a simple form of machine by which a single operative can rapidly, accurately and eiliciently insert the plugs without the use of any particular skill.

The invention in its main feature provides an expan'sible hollow finger tapered to permit it to enter the article into which the plug is to be inserted and preferably hav ing its nose made up of a plurality of thin metal platesand preferably when used in connection with helmet sweat-bands tapered to a thin flat point enabling it to enter a slit, and the invention further provides a plunger reciprocable longitudinally within this finger acting to force the plug which is fed into the finger through its side out through the expansible finger into the article into which it is to be inserted, and the invention further provides a positioner on this plunger to engage the article at some defined point such, for example, as the edge of the slit and thus define the position of the plug in the article.

The invention also provides suitable means for successively feeding the plugs into the tapering finger.

These and other objects and features of the invention will appear more fully from the accompanying description and drawings and will be particularly pointed out in the claims.

In the drawings,

Figure l is a side elevation partially broken away of a simple form of machine embodying a preferred form of the invention;

Fig. 2 is a plan view of a section of the sweat-band structure for use in a steel helmet showing a plug in place in one section thereof;

Fig. 8 is a transverse section taken on the line 33, of Fig. 2';

Fig. l is a top plan view of the forward end of the plunger with a plug in position thereon shown in cross-section;

Fig. 5 is an enlarged side elevation of the central portion of the machine where the plug is fed in front of the plunger, and of the finger, with some of the parts shown in central vertical section;

Fig. 6 is ,a transverse section taken on the line 6-43, of Fig. 5; c

Fig. 7 is a view in perspective of a por tion of the sweat-band and the end of the fin er show-nu the artsafter the fin erhas 24 screwed thereto and to the base.

Fig, 11 a View in Side elevation Of 8. portion of the machine showing a different form of agitator.

While it is to be understood that the in vention in its broader aspects is not to be limited to the particular kind of plug hanlled nor the particular kind of article into which the plug is inserted the invention is particularly designed as already pointed out for inserting hollow cylindrical rubber plugs into sweat-bands for steel Army helmets and the machine herein illustrated embodying a preferred form of the invention is particularly designed for that specific purpose.

The sweat-band. structures include two strips of material. One of these strips 12 is usually formed of leather and the opposing or juxtaposed strip 13 may be of a composite structure or of suitable material. VLines of stitching 1 f unite these strips together and thus leave between the st ips and bounded by the stitching a space which is utilized for the section of resilient or elastic plugs. The strip of leather 12 is provided with transverse slits 15, the distance between these slits usually being slightly greater than the length of the plugs. When the operation is performed by hand the operative usually places the plug on the butt end of a needle or bodkin and pulls the needle or bodkin into one of the slits and out of the other forcing the plug in after it. The length of these slits is usually somewhat less than half the circumference of the plugs so that the operation is somewhat difficult and requires considerable time.

The plugs such as ommonly used are small, hollow cylinders of rubber 16 or similar material and when in place form a very satisfactory elastic buffer.

The machine herein illustrated is shown as having a solid base 17 which may be bolted by bolts 18 to a table or other suitable support. At one side an arm 19 rises vertically from the base to support the hopper containing a supply of plugs and at the other side a bed plate 20 projects laterally from the base and is supported by a bracket 21.

The forward portion of the base is recessed and the rearward portion of the base is cut away to provide a flat surface 22 running through the length of the base.

In this recessed portion of the base at the forward end the finger is rigidly mounted. This finger in the preferred construction illustrated comprises a head 23 and a nose which is the expansible part of the finger.

The head 23 is preferably formed of a square bar of metal with a cylindrical longitudinal bore to receive the plunger and is secured in place in the recess in the base by angle plates At its forward end the head 23 is provided with exterior tapering seats. On the upper and lower seats are secured thin fiat metal plates 25 and these plates are held in place by screws 26. On the lateral seats are secured similar thin flat metal plates 27 but these latter plates shorter and narrower than the plates 25 and extend between the plates 25 when the parts are in normal position. These four plates make up the nose or eX- pansible portion of the hollow finger and when in normal position the plates 25 contact at their forward ends and present a thin fiat point or edge well adapted to enter a slit or narrow opening. At the sides the plates 27 fit in between the plates 25 as shown in Figs. 5 and 6 and the four plates together bound a central opening which is a continuation of the opening in the head portion 23.

The plunger 28 reciprocates longitudinally within the finger and is preferably of cylindrical cross section. At its forward end it is preferably of substantially the diameter of the plug to be inserted and in the case of a hollow plug may be provided with a stud 29 adapted to fit within the plug and support the plug in place.

This plunger may be reciprocated by any suitable mechanism and at a speed suitable to the requirements of the operator.

A main shaft 30 is mounted transversely in hearings in the plate 20. This plate is slotted vertically and in the slot on the main shaft is mounted a pulley 31 driven from a suitable source of power. At its inner end the main shaft carries a crank arm 32 piv oted to a link 33 which in turn is pivoted to a sleeve 34 mounted on the rear end'of the plunger 28. Thus as the main shaft is retated the plunger is reciprocated. Suitable bearings are provided such as 35 for the support and guidance of the rear end of th plunger. I

At its forward end the plunger is provided with a positioner to engage the article into which the plug is to be inserted and define the position of the plug therein. This positioner also serves to remove the work from the nose of the finger leaving it free in the operatives hands ready for the next insertion. In the construction illus trated this positioner is shown as a bar or pin 36 set into the plunger and extending transversely thereof a slight distance back of the end. The head 23 of the finger is transversely slotted at 37 to provide for the movement of the positioner in the reciprocation of the plunger.

The plugs are supplied successively through the side of the linger in front of the plunger when the plunger is in its retracted position and this may be done by any suitable mechanism. In the construction illustrated the head 23 of the finger is provided with an opening 38 on its top face of sufiici nt size to allow a plug to pass therethrdugh when in lengthwise position. Consequently when the plunger is in retracted position as shown in Fig. 5 the plug 16 shown in dotted lines will lie in the head of the finger directly in front of the plunger and as the plunger projected the stud 29 will. enter the-naperture in the plug and the forward end of the plunger contact with the end of the plug so that as the projection of the plunger continues the plug will be forced into and through the expansible or resilient forward portion of the finger.

A. vertical guideway shown as a metal tube 39 of slightly larger internal diameter than the plugs is supported in a vertical position above the head 23. directly in the rear of the opening 38. This tube is flanged at l0 and secured in position by screws ll passing into the head 22-3. On its opposite or front face this tube is opened as by bending forward thewalls to provide a guiding aperture of suflicient size to allow the plugs to pass out forwardly over the aperture 38.

The tube 239 extends upwardly and is secured, in place by a suitable bracket d3 passing through the arm 19 and at its upper end it terminates in a hopper e l also secured to the arm 19. This hopper is of sullicient size to hold a substantial number of the plugs and is filled from time to time by the operative.

The plugs are agitated in the hopper by suitable means so as to cause them to slide endwise in the tube 39 and stand in the tube one on top of the other as indicated in dotted lines in Fig. 9, thus providing a continuous procession of plugs in the tube. One form of agitator is shown as a wire member iii) of helical form which is continuously rotated about its axis. For this purpose it is shown as connected to a vertical shaft 46 mounted in. a plate l7 extending laterally from the arm 19. This shaft may be driven inany suitable manner from the main shaft 30 and for that purpose is shown as provided with a pulley d8 around which a belt 49 runs over idlers 50 to a pulley 51 on the end of the main shaft.

Another form of agitator is shown in Fig. 11. In this case a bracket supports a transverse shaft 53 carrying curved agitating arms at which enter through a slot at the lower end of the hopper 14:. The shaft may be turned by a pulley 55 belted to thepulley 51. In this case the shaft 53 is rotated clockwise and the arms 521; lift or agitate the plugs in the hopper and secure their passage in procession into the tube 39.

The lowermost plug in the tube 39 rests upon the top of the head 23 and preferably over a small projection 56 upstanding therefrom.

In order to feed the plugs successively from the tube 39 through the aperture opening 38 in frontof the plunger the plunger is shown as provided with a sleeve 57 and a pusher rod 58 is adjustably secured in this sleeve by a set screw 59 so that the pusher rod extends parallel to the plunger. This pusher rod at its forward end passes through a small aperture 60 in the rear wall of the tube 39 and is positioned so as to come opposite the top of the lowermost plug in the tube. When the plunger is in retracted position the forward end of this pusher rod is behind the rear wall of the tube. As the plunger in its reciprocation approaches the end of its projecting movement the endof the pusher rodcomes against the upper end of the lowermost plug in the tube and tips it forwardly about the projection 56 and, guided by the forward walls l2 of the tube, the plug thereupon falls over intohorizontal position anddrops through the aperture 38 and lies on top of the projected plunger.

t is further guided and assisted'in falling by a vertical guide plate 61 secured to the head 23 by one of the screws 26 in front of the aperture 38. On the next retracting movement of the plunger the pusher rod first withdraws from the tube allowing the next plug to drop onto the projection 56. After the forward end of the plunger has passed the aperture 38the plug which has been resting on the plunger drops down into the head 23 in front of the plunger.

The plunger is maintained in axial posi tion andprevented fromturning by a projection 62. on the sleeve 5'7 riding in a slot'GS in the base.

The operation of the machine will now be apparent. hen in the rotation of the main shaft the plunger has withdrawn to its retracted position the operative located in front of the machine seizes the article such as the sweat-band structure and pushes it over the tapering end of the enpansible finger. In the case of the slotted strip it is thus very easy for the operative to push one of the slits 15. over the flat thin tapered point formed by the two blades 25 until the forward end of the finger passes through one slit and out through the next slit as shown in Fig. 7 This operation is readily, easily and rapidly performed by the operative.

The operativecontinues to hold the article'and as the main shaft revolves the plunger 28 with the connected pusher rod 58 is projected. As the projecting movement con tinues the stud. :29 enters the hole in the plug, the forward end of the plunger comes in contact with the rear end of the plug and the plug then as a part of the plunger is carried forwardly between the plates 25 and 27 and expands or opens these plates thus expanding or opening the finger, and as the movement continues the plug is pushed out of the forward end of the plates which at the same time expand and open up the slits in the article until the plug is forced into place in the article. It is so arranged that as the plug reaches its seat in the article the positioner 36 contacts with the article, and in this case with the rearward edge of the section 64. When the positioner contacts with this edge the plug is then correctly seated and as the plunger continues its movement, it pushes the article away from the finger. As the plunger nears the end of its projecting movement the forward end of the pusher rod enters the tube 39 and'tips over the lowermost plug causing it to fall through the aperture 38 and rest upon the top of the projected plunger ready to fall into feeding position when the plunger is retracted. As the retracting movement begins the pusher rod immediately withdraws from the tube and a successive plug falls into place over the projection 56. On the next reciprocation the operation is repeated.

Having fully described my invention, what I claim as new and desire to secure by Let ters Patent is:

1. A machine for inserting plugs compris-- ing an eXpansible hollow finger tapered to permit it to enter the article into which the plug is to be inserted and open a seat for the plug, a plunger reciprocable longitudinally within said finger and a positioner on the plunger to engage the article and define the position of the plug therein.

2. A machine for inserting plugs as clefined in claim 1 together with means for successively supplying plugs through the side of said finger in front of said plunger when retracted. V

8. A machine for inserting plugs comprising an eXpansible hollow finger tapered to a flat point to permit it to enter a slit in the article into which the plug is to be inserted and open a seat for the plug, a plunger reciprocable longitudinally within said finger, and a positioner on the plunger to en gage the ec ge of the said slit and define the position of the plug in the article when forced out of the finger by the plunger.

4. A machine for inserting plugs as defined in claim 3 together with means for successively supplying plugs through the side of said finger in front of said plunger when retracted.

5. A machine for inserting hollow plugs, comprising an expansible hollow finger tapered to permit it to enter the article into which the plug is to be inserted and open a seat for the plug, a plunger provided at its forward end with a stud to enter and sup port a hollow plug and reciprocable longitudinally within said finger, and a positioner on the plunger in the rear of the said stud to engage the article and define the position of the plug therein.

6. A machine for inserting plugs comprising a base, a longitudinally bored finger head rigidly secured in said base, a plurality of thin flexible tapering plates secured to said head and projecting to form a tapering hollow nose, and a plunger reciprocable longitudinally within said finger and adapted when the said nose has been inserted into the article into which the plug is to be inserted to force the plug through the expansible nose into the said article.

7. A' machine for inserting plugs as defined in claim 6 together with a positioner on the plunger to engage the article and define the position of the plug therein.

8. A machine for inserting plugs comprising a base, an eXpansible hollow tapered finger rigidly secured in said base, a plunger reciprocable longitudinally within said finger, an opening through the wall of said finger in front of the plunger when in retracted position, a feed tube for the plugs in rear of said opening, and means operated by the plunger for pushing the lowermost plug from said feed tube into said opening near the conclusion of {projecting movement of the plunger, whereby a plug will fall in front of the plunger when retracted and be forced at the next projection of the plunger through the tapered finger into position in an article into which the finger has previously been inserted.

9. An expansible hollow finger for use in a machine for inserting plugs comprising a hollow head, a pair of thin flexible metal plates secured to and projecting from said head at opposite sides thereof, a pair of thin .fiat tapering metal. plates secured to said head at right angles to the first plates, and projecting forwardly from said head between said plates, the said four plates together forming an eXpansible nose having a thin fiat penetrating end.

In testimony whereof I have signed my name to this specification.

MERTON W. HOWARD. 

